In life to correct the situation of patients breathing with the mouth at night, we must pay attention to the following aspects of the reasons: first, we must pay attention to the sleeping position, avoid excessive head back, try to use the side lying position, which can effectively improve the patient open mouth breathing situation. Second, the patient needs to pay attention to ensure nasal ventilation, when the patient’s nose is well ventilated to be able to breathe without the mouth, if the patient has rhinitis, can be sprayed with tretinoin nasal spray, or fluticasone propionate spray to treat. Thirdly, the main consideration is that the patient’s teeth are not bitten together before the open mouth breathing situation occurs. It is recommended to go to the stomatology department for active correction so that the nose will be shut up to breathe when sleeping, and the symptoms will improve with active symptomatic treatment.